1. Field of the Invention
This invention relates to apparatus for delivering fluid drugs, medicaments or other medicinal liquids to a desired location within a human body and more particularly relates to means for securing such a device within a pocket of tissue of other similar location within a body.
2. Description of Related Art
A number of approaches have been followed in the prior art for the dispensing of medical substances in the body. One particularly effective method has been to implant a reservoir of fluid medical substances and a pump in a patient""s body. The reservoir and pump are connected to a catheter that delivers the fluid medical substance to a desired location in the body.
A number of reservoirs, pumps and combinations of reservoirs and pumps have been developed. For example, U.S. Pat. No. 3,527,220 shows an implantable drug administrator that operates with a refillable bladder reservoir and a roller pump that is driven by a magnet located outside the body. U.S. Pat. No. 3,951,147 shows a reservoir formed from a bellows enclosed within a housing. The contents of the reservoir are pressurized by a fluorocarbon fluid located in the space between the housing and bellows. The unit continuously dispenses the liquid to the body site through a capillary tube.
U.S. Pat. No. 4,146,029 shows a dispenser that dispenses drugs in a predetermined manner which may be modified somewhat by means external to the body. A piston and bellows pumping device is used to dispense the drug.
Additional pumps and reservoirs are shown in U.S. Pat. No. 4,931,050, issued Jun. 5, 1990 to Samir F. Idriss entitled xe2x80x9cConstant Pressure Variable Flow Pumpxe2x80x9d; U.S. Pat. No. 4,838,887, issued Jun. 13, 1989 to Samir F. Idriss entitled xe2x80x9cProgrammable Valve Pumpxe2x80x9d; U.S. Pat. No. 5,207,666, issued May 4, 1993 to Samir F. Idriss and Joshua Makower entitled xe2x80x9cPassive Shuttle Metering Device For Implantable Drug Delivery Systemxe2x80x9d; U.S. Pat. No. 4,714,462, issued Dec. 22, 1987 to Robert A. DiDomenico entitled xe2x80x9cPositive Pressure Programmable Infusion Pumpxe2x80x9d; and U.S. Pat. No. 5,176,641 issued Jan. 5, 1993 to Samir F. Idriss entitled xe2x80x9cImplantable Drug Infusion Reservoir Having Fluid Impelling Resilient Foam Memberxe2x80x9d.
Further pumps and reservoirs are shown in U.S. Pat. No. 5,575,770 issued Nov. 19, 1996 to Gerald S. Melsky and Bradley J. Enegren entitled xe2x80x9cImplantable Drug Infusion System With Safe Bolus Capabilityxe2x80x9d; U.S. Pat. No. 4,978,338 issued Dec. 18, 1990 to Gerald S. Melsky and Frank R. Prosl entitled xe2x80x9cImplantable Infusion Apparatusxe2x80x9d; U.S. Pat. No. 5,908,414 issued Jun. 1, 1999 to Karl-Heinz Otto, Manfred Wieland, Hans Baumann and Jorg-Roger Peters entitled xe2x80x9cImplantable Infusion Pumpxe2x80x9d; and U.S. Pat. No. 5,769,823 issued Jun. 23, 1998 to Karl-Heinz Otto entitled xe2x80x9cImplantable Infusion Pumpxe2x80x9d. The collective teachings of the patents listed above are incorporated herein in their entireties by reference.
A reservoir and pump system for storing and delivering fluid medicaments to a desired location in a body is shown schematically in FIG. 1 generally labeled 10. System 10 has a pump 12 that stores and dispenses fluid medicaments. A catheter 14 is connected to pump 12 and carries the fluid medicament from the pump 12 to a desired location in a body. The pump 12 and catheter 14 are implanted within the body.
Pump 12 typically has a primary septum 16 through which a drug, fluid or other medicament is placed in the pump 12. Pump 12 may also have a bolus septum 18 through which a bolus injection of drug, fluid or other medicament may be administered to the patient through the catheter 14.
Pump 12 is typically implanted in a body by creating a pocket in the tissue of the patient and placing the pump in the pocket. The pocket is often located under the skin in the abdomen below the rib cage. It is important that the pump 12 stay within the pocket so as not to migrate and maintain a desired orientation so as not to become separated from the catheter 14. To this end, the pump 12 is often sutured in the pocket to the surrounding tissue. In this way, the pump 12 cannot move within the pocket.
To facilitate the suturing, as shown in FIGS. 2-4, a series of suture loops 20 are placed on the outside of the pump 12. These suture loops 20 are typically made of wire that are fastened to the outside surface 22 of the pump 12 at each end 24 of each suture loop 20 by means such as welding. As a result, suture loops 20 are attached to the outside surface 22 of pump 12 at each end 24 of suture loop 20 and extend a small distance from the outside of pump 12 between the ends 24 of suture loop 20. As a result, a space 26 is formed between the outside surface 22 and the suture loops 20.
The surgeon, after placing pump 12 within the pocket xe2x80x9cAxe2x80x9d (FIG. 5), places a suture through the tissue and through the space 26 formed between the outside surface 22 and the suture loop 20 and ties a knot to secure the pump in a fixed position relative to the pocket. Because the suture is placed between the outside surface 22 and the suture loop 20, the suture is constrained to remain in the space 26. As a result, as the surgeon snugs up the suture and ties the knot, the suture is brought into taught engagement with the suture loop 20 whereby the pump is securely positioned.
One problem with this configuration is that suture loops 20 extend away from the outside surface 22 of pump 12. As a result, the ultimate dimensions of pump 12 with suture loops 20 are enlarged from the dimensions of the outside surface 22 of pump 12 itself. This then requires a slightly larger pocket to be created to hold the pump 12 with the suture loops 20 than would be necessary if pump 12 without the suture loops 20 were used. Further, the protruding suture loops 20 sometimes jab into and irritate the tissue of the pocket surrounding the suture loops 20. These are problems in want of a solution.
A pump for pumping drugs, medicaments or other liquids is disclosed in one embodiment having suture loops co-extensive with the outside surface of the pump. At least one depression is formed in the outside surface of the pump. A suture loop, preferably in the form of a wire, co-extensive with the outer dimensions of the pump passes over the depression forming a space between the wire and the outside surface of the pump in the depression. In this position, the wire forms a suture loop. The surgeon, when suturing the pump of the present invention in place within a pocket of tissue or other similar location, places a suture between the wire and the outside surface of the pump in the depression to secure the pump.
In an alternate embodiment, depressions are created in a pump and a soft material is placed in and attached to the depressions. A suture may then be placed through the material of the soft material and the tissue of the patient in a pocket in the tissue of the patient to affixed the pump in the pocket.
It is therefore an object of the present invention to provide a pump that may be sutured in a pocket of tissue of other similar location in a body where the pump does not have any substantial protrusions from its outside surface to facilitate the pump being sutured in the desired location.
It is another object of the invention to provide a system to facilitate suturing the pump in place in a desired location that is relatively easy to manufacture.
These and other objects of the invention will be clear from the description of the invention contained herein and more particularly from the description in conjunction with the drawings attached hereto. Throughout this description, wherever referred to, like elements are referred to by like reference numbers.